HDINLINE float_X operator()(const float_X x)
{
/* -
* | 1/6*(4 - 6*x^2 + 3*|x|^3) if 0<=|x|<1
* W(x)=<| 1/6*(2 - |x|)^3 if 1<=|x|<2
* | 0 otherwise
* -
*/
float_X abs_x = algorithms::math::abs(x);
const bool below_1 = (abs_x < float_X(1.0));
const bool below_2 = (abs_x < float_X(2.0));
return float_X(below_1) * ff_1st_radius(abs_x) +
float_X(below_2 && !below_1) * ff_2nd_radius(abs_x);
}
/** form factor of this particle shape.
* \param x has to be within [-support/2, support/2]
*/
HDINLINE float_X operator()(const float_X x)
{
/* -
* | 3/4 - x^2 if |x|<1/2
* W(x)=<|
* | 1/2*(3/2 - |x|)^2 if 1/2<=|x|<3/2
* -
*/
float_X abs_x = algorithms::math::abs(x);
const bool below_05 = (abs_x < float_X(0.5));
const float_X fbelow_05 = float_X(below_05);
return fbelow_05 * ff_1st_radius(abs_x) +
float_X(!below_05) * ff_2nd_radius(abs_x);
}
HDINLINE float_X operator()(const float_X x)
{
/* -
* | 1/6*(4 - 6*x^2 + 3*|x|^3) if 0<=|x|<1
* W(x)=<|
* | 1/6*(2 - |x|)^3 if 1<=|x|<2
* -
*/
float_X abs_x = algorithms::math::abs(x);
const bool below_1 = (abs_x < float_X(1.0));
return float_X(below_1) * ff_1st_radius(abs_x) +
float_X(!below_1) * ff_2nd_radius(abs_x);
/* Semantix:
if (abs_x < float_X(1.0))
return ff_1st_radius(abs_x);
return ff_2nd_radius(abs_x);
*/
}